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B12 advice

Molly161018 profile image
8 Replies

I'm new to this forum - have been on the thyroid one for a few years, and it has been suggested that I may have PA.

However I supplement with a B complex so levels are ok. However they have gone up and down a lot, and despite increasing my dose it hasn't increased my levels, so makes me wonder if I have an absorption issue.

Anyway, having spoken to my GP, he was actually quite helpful and has suggested I come off my b complex for a month or two and then have a blood test.

I'm a bit worried about doing this, as I've got enough symptoms without coming off it, but I guess I haven't got much choice...

So I have a few questions...

- how long would it take to get the supplemented b12 out of my system?

- the Dr didn't make anything of the variations in my levels previously, just said testing every 3 months was too often and you will get variations...is this correct? See attached pic of graph

- can you have absorption problems even though the blood levels look ok?

Would be glad of some advice

MT in advance 😊

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Molly161018
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8 Replies
Nackapan profile image
Nackapan

If functional b12 deficiency is suspected an MMa test csn be done.A Intrinsic factor antibody test if positive will confirm PA

However seems to only pick up about 50% of those that have it.

Alot of symptoms overlap with other conditions

It seems as though you are absorbing from oral B12

Does it actually help symptoms??

It woukd be great if you couod cope on oral b12 .

B12 injections fof life necessary with PA

Also for those of us started on b12 injections ax per guidelines when very ill and a very low serum b12 level.

A few csn revert back to daily oral b12 that's usually If the cause is dietary.

Every 3m b12 testing will give variations but with your graph an overall level coukd be worked out.( mean)

Main thing is to go by symptoms.

Did you get a baseline level of b12 before supplements started?

Is folate ,vit d ,ferritin snd iron

Not sure how long your b12 will take to drop after stopping supplements.

It differs I think.

The Gps love numbers.

It depends how bad you get off supplements.

If they work why csnt you just carry on with your regime?

What dose of b12 is in your supplements?

Molly161018 profile image
Molly161018 in reply toNackapan

Thanks Nakapan,

So an MMA test can be done without coming off my supplements can it?

Yes I guess I am absorbing from the oral supplement, but why have my levels not increased with my dose increase?

My base level in 2019 was 93pmol/L, but the lowest it dipped to was 70.4pmol/L in 2022, despite taking the b complex which contains 400mg. This was when I increased my dose to two capsules (800mg per day). It then increased for two consecutive tests, up to 136pmol/L, but back down to 82pmol again in March this year.

The reason I'm on here is that I feel my current regime is not working...I have various symptoms - lethargy and tiredness, tension headaches, brain fog, auto immune condition (autoimmune underactive thyroid), shortness of breath, joint pain, yellowish skin, bruise easily and for no reason, heavy periods, low libido, likely PCOS.

And yes my folate, vitamin D, ferratin and iron are all alright...

jade_s profile image
jade_s

Hi Molly, nackapan gave good suggestions for testing.

- how long would it take to get the supplemented b12 out of my system?

Some people say a minimum of 4 months, and up to 6 months for some. A long time to wait if you're deteriorating. An alternative is to get all the testing done and then try injections to see if they help (what i did, but i was quite bad despite taking sublingual b12 for years - more on that below).

- the Dr didn't make anything of the variations in my levels previously, just said testing every 3 months was too often and you will get variations...is this correct? See attached pic of graph

In general, for a healthy person, if you start & stop supplementing then levels will likely go up & down. I have a hard time reading your graph though - no values on the y-axis and impossible to tell how much it's changing.

Were you supplementing the whole time & how much b12 in the complex?

How are your folate levels?

What are your symptoms?

- can you have absorption problems even though the blood levels look ok?

Absolutely. My blood levels were really high but i was still functionally deficient. My arms from elbow to fingers went totally numb. My MMA & homocysteine were normal. Antibodies negative. A trial of injections helped so that was my answer.

But often MMA &/or homocysteine will be out of range with functional b12 dediciency.

I agree with nackapan, go by symptoms. A symptoms log is always a good idea.

Molly161018 profile image
Molly161018 in reply tojade_s

Thanks JadeYes I agree 4-6 months will be a long time to wait if I'm feeling rubbish!! 😫 Especially when trying to keep up with a toddler and moving house!!

Sorry yes the graph doesn't mean much without axis! At my first test in 2019 it was 93pmol/L, and this is when I started supplementing.

The lowest it dipped to was 70.4pmol/L in 2022, despite taking the b complex which contains 400mg. This was when I increased my dose to two capsules (800mg per day).

It then increased for two consecutive tests, up to 136pmol/L, but back down to 82pmol again in March this year.

Hope that helps answer your questions!

I have various symptoms - lethargy and tiredness, tension headaches, brain fog, auto immune condition (autoimmune underactive thyroid), shortness of breath, joint pain, yellowish skin, bruise easily and for no reason, heavy periods, low libido, likely PCOS.

And yes my folate levels are good (however 2 x b complex contains 1334mcg and I also take a separate folate supplement of 400mcg to get any kind of decent level!)

Your experience of high levels and yet being functionally deficient is very interesting... I'm wondering about going to a private GP...at least I should be able to request the tests I need rather than come off my supplements only to risk being told it's all fine anyway by my NHS GP...but I hate to think what the tests might cost 😑

So am I right in thinking an MMA test could flag up an absorption problem even if I continue supplementing?

I wonder what tests the GP was planning on doing after coming off them? If it's an MMA anyway (and my assumption above is correct) then I guess I could still go for the test but not stop my b complex like he suggested...

Not sure if I'm making any sense...🥴

jade_s profile image
jade_s in reply toMolly161018

Symptoms-wise it's hard to say - a lot of those sound like hypothyroid symptoms but as we all know, symptoms tend to overlap. Do you have any tingling, pin'n'needles, electric shocks, bugs crawling sensation, itching, swaying while walking or going up stairs, losing balance easily, vertigo/dizziness? Those are some typical b12 deficiency neurological symptoms. Do check out this symptoms list: b12deficiency.info/signs-an... .

If you don't have any of these major neurological symptoms, then I agree with your doctor - it might be worth stopping supplements and then test MMA, homocysteine, Intrinsic factor and gastric parietal cell antibodies, and folate within a few months. I would also get a standard serum B12 test in addition to active B12.

Continuing supplements will further complicate testing. Although the dose in your B complex is not high (I assume you mean 400 mcg, not mg), it can still interfere with testing - as you can it already seems to affect active B12 to some extent. I would also stop supplements with folate / folic acid - this is because it will normalize the hematological signs of B12 deficiency (B12D), such as high MCH, and hide B12D. And if you really do have an absorption problem, I can't imagine that 400mcg was doing much anyway.

If you're impatient (as we all understand and know how bad B12D feels!), you could go ahead with testing now *if* you can get your doctor to agree to retesting again after a few months. If you have an absorption problem, B12 levels should drop significantly. However if they're all 'normal' then you will have to decide whether to wait a few more months, trial higher doses of oral B12, or consider a trial of injections to see if they help (that's what I did). B12 is weird one, and testing doesn't always show what's happening at the cellular level. In those cases, symptoms are important, especially the ones we call "neurological" ones.

Have you ever had high MCV or high MPV prior to starting the B complex? High RDW?

I assume iron, Vit D, electrolytes, are all OK? Have you every had a fasting early morning cortisol test? Have they tested Calcium levels?

Sorry, it's not easy I know. I hope this helps a bit.

Gambit62 profile image
Gambit62Administrator

serum B12 is only accurate to about 20% - though levels for B12 tend to be pretty constant - the results of serum B12 will tend to be up and down because of this.

If your blood tests are showing a significant (>20% fall in levels) consistently over time that would indicate an absorption problem.

A couple of months may or may not be long enough for any excess to clear your system as people vary a lot in how long it takes. if you have been taking oral supplements this is the minimum time.

interpreting the results if above if you are supplementing is at best difficult because you don't have a baseline, there are likely to be variations in the dosage in the supplements you are taking which would also affect levels.

Molly161018 profile image
Molly161018 in reply toGambit62

Hello Gambit

Many thanks for your helpful reply.

From December 22 to March 23 (my latest drop) it went from 136 pmol/L down to 82 pmol/L, so yes more than a 20% drop...and the previous fluctuations have been of similar size ...but would it need to be a consistent drop to show absorption issues, as my levels go up and down?

Gambit62 profile image
Gambit62Administrator in reply toMolly161018

strictly 20% applies to serum B12 rather than active B12

Yes, it would need to be a continuous downwards trend (in the absence of supplementation) to demonstrate an absorption problem

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